Your kid not doing so hot in math? Don’t count on seeing a C or D. Look for an N instead.

The Montgomery County public school system is joining other districts across the country in abandoning traditional letter grades for some students and instead matching student evaluations with specific curriculum standards.

Instead of seeing A’s, B’s, C’s or D’s on report cards this November, for the first time, parents of Montgomery students in third grade will see ES, P, I or N. Those new letters will also apply to students in first through second grade, who used to get O’s, S’s or N’s.

Teachers also will mark students separately on learning skills such as “effort,” “intellectual risk taking” and “originality” with separate codes of DEM (demonstrating), PRG (progressing) or N (not yet evident).

Although the first report cards under the “standards-based” grading system aren’t due for about a month, the dramatic shift is worrying parents in the high-achieving school district who are concerned that their children can’t earn straight A’s or land on the traditional honor roll. Parents also are confused about how to use the information from the new report cards to help their kids do better in school.

District officials say the switch, which will eventually also apply to fourth- and fifth-graders, will give parents more details about their children’s academic performance and provide more rigorous standards for what being “proficient” in a subject area means.

After being piloted at 25 schools in the past five years, the new report cards will be used at all 132 elementary schools in the district this fall. Officials adopted the standards-based report card to match the county’s new curriculum guidelines for elementary schools, called Curriculum 2.0.

In the old system, students received a single letter grade in a subject area, such as math, social studies or reading. On the standards-based report card, each subject area is broken down into several categories. For example, social studies is divided into “measurement topics” of civics, culture, economics, geography and history.

Teachers mark students with an ES, P, I or N in each category to indicate how close students are to mastering what they should know by the end of the school year. ES means “exceptional,” P means “demonstrating proficiency,” I means “in progress,” and N means “not yet making progress or making minimal progress” toward meeting standards.

Parents of kindergartners will still see P, I and N, but won’t get the new, more detailed report cards until December.

Langford-Brown said the switch is aimed at offering a more accurate assessment of how well students understand concepts. There isn’t a one-to-one comparison between the traditional letter-grade system and the new report card, she added — an ES isn’t the same as an A, a P isn’t a B.

For example, a student who gets a question wrong on a 10-question test would get an A under a traditional grading standard. But the question the student got wrong may be measuring a more complex application of a skill, rather than simply asking students to recall a fact. If a student can’t apply what they’ve learned, they might receive a P, not an ES.

In other words, moving to a standards-based report card is about the quality of information, not quantity, said Samantha Brown Olivieri, with California-based GreatSchools, a nonprofit that helps parents take a more active role in their children’s education.

Olivieri said more schools across the country are moving toward standards-based report cards to align with the adoption of Common Core standards, which focus on critical thinking and other higher-order skills students are expected to have in the “real world.”

Locally, Fairfax, Loudoun and Prince William counties have implemented or are planning to implement versions of standards-based report cards.

“It’s not just about what letter we’re using or the grading systems,” Olivieri said. “It’s about the information inspiring action from parents to support their kids.”

Some parents think the overhaul of the grading system is a waste of time.

White said she likes the new curriculum standards, but the new grading system looks like it’s just switching out A through E with a new set of letters.

“For her spelling test, my daughter came home with an I, and to me, I saw it and just [said], ‘That’s a C,’ ” White said.

Kelley Rogers is the parent of a fourth-grader at Darnestown Elementary School, one of 25 campuses that has been piloting different standards-based report cards.

She said the new system isn’t as “predictive” and makes it difficult for her to understand exactly how her child is doing in class.

“It does seem squishy,” Rogers said. “It bothers some parents a lot because they want to know what to tell their child to do differently . . . and there’s not always guidance for that.”

Darnestown Principal Laura Colgary said the most challenging part of the switch has been communicating changes without overwhelming parents.

“It’s helping parents to understand really what the grades mean on the report card and let them know they’re getting more information than they’re used to,” Colgary said.

Montgomery has a 10-minute online video tutorial explaining the new grades for parents.

Colgary recommends that parents study the district’s curriculum standards for their children’s grade levels and connect that information with what they’ll be seeing on report cards in November.

“Making the link between the curriculum and what is being reported will be helpful,” she said. “It won’t be meaningful without the background information.”

Langford-Brown said the county aims to roll out the new report card to fourth- and fifth-graders in the next few years, though there is no specific timeline. That means all of the more than 66,000 elementary school students in Montgomery will be on the standards-based report card soon.

Rogers’s advice for parents: “Take a deep breath. There is a lot of information.”